Piston-control mechanism



Aug. 7, 1923.

R. H. ANNHSON I PISTON CONTROL MECHANISM Filed June 23, 1920, s Sheets-Sheet 1 Aug. 7, 1923.

' H. ANNIISON 4 PISTON CONTROL MECHANISM s Sheets-Shet 5 7 Filed June 23, 1920 5 3 MM IN Patented Aug. 7, 1923.

UNITED STATES PATENT OFFICE.

RICHARD TIE'NRY ANNISON, or LONDON, ENGLAND.

PISTON-CONTROL MECHANISM.

T ojall whom it may con ern.-

Be it known that I, RIoHAnn HENRY AN- Ni'soN, subject of the King of Great Britain and Ireland, residing at London, England, have invented certain new and useful Improvements in Piston-Control Mecha nism (for which I have filed application in Great Britain March 22, 1919, Patent 150,010), of which the following is a specification. I

This invention relates to improvedmeans for controlling pistons in cylinders for use in connection with pile drivers, hammers, pile extractors and the like apparatus and refers to apparatus of this kind wherein the cylinder is provided with a series of sebarately closable ports in communication with a valve chamber, the ports being arranged longitudinally of the cylindeiyso that the stroke of the piston may be varied by varying the point of exhaust from the cylinder.

The invention has for its object an improved construction of apparatus of this type and relates more particularly to special and advantageous constructions and applications of the invention to pile drivers, pile extractors, hammers, and the like apparatus.

According to the present invention, the cylinder is provided with one or more passages leading toa valve chamber through which operating fluid controlling the movement of the valve as admitted, one or each of said passages having a plurality of separately clos'able ports arranged longitudinally of the cylinder co-operating with one or more chambers in the periphery of thepis'ton, whilst the cylinder is also provided with separate and independent passages leading to opposite ends or the cylinder through which operating fluid is admitted and emitted from opposite sides of the power cylinder. The steam or other motive fluid is admitted alternately at each end of the piston, and the exhanstopened at the appropriate times, in the ordinary way, the separately closable ports permitting the timing of the admission and exhaust to be varied as regards the length of the cylinder, so that the stroke of the piston can be altered and eonsequenu the blow or other effort of the machine varied to suit requiremerits.

For controlling the admission and exhaust I provide suite-i118 Valves but preferably Application filed June 23, 1920. Serial No. 391,199.

(GRANTED UNDER THE PROVISIONS or THE ACT or Manon 3, 1921, 4.1 STAT. L., 1313.

a semirotary valve, which alternately aol- Inits the pressure fluid to each side of the piston and opens the corresponding exhaust, the valve being automatically operated by the pressure fluid when the piston reaches each end of its stroke, which stroke may be varied as just explained.

In order that the general .it'eatures of my lnvention may be understood I will now describe the same as applied to the piston of a pile driver or pile extractor. I

The semi-rotary valve which I prefer to employ is contained in a suitable casing having inlet and outlet passages for the operating fluid. The valve comprises two discs or drums with a spindle between them, and so attached thereto that they can be readily separated and removed from the casing, the spindle being preferably of smaller diameter than the disc.

These discs or drums have a plurality of pockets or recesses in or upon part of their periphery, each balancing the other. In a similar way the edge of the periphery opposite to the pockets may be cut away or slotted to form a recess engaging with a stop. or stops provided in the casing for the purpose of stopping the rotation at the desired point.

I may further provide a small passage in or across each disc from one or more of the quantity oi the operating fluid to cushion the shoulder of the disc or discs against the stops provided for it.

The spindle may also have two or more ports or openings through or across forming two way or three way passages. Preferably there are four through passages kept fluid tight from each other and their adjoining discs by means of piston rings or other means or combination of means. The tour spindle ports lead to two bridged ways for the admission and. emission of fluidto and from the passages leading to the cylinder, for the operation of the piston therein.

In the case of four ports, one-each "of one pair acts in concert alternately with one of the other pair and by the use of four, the admission port leading to one end of the cylinder body m'ay be larger than'the other and the ones for the exhaust varied in like manner.

The piston in the cylinder has part of its body cut away at each end to admit the operating medium or the cylinder cover or both may be recessed for the same purpose. The intermediate portion of the piston body is also cut away or recessed, forming one or more chambers between it and the cylinder wall for the supply of the operating fluid to rotate the discs through suitably placed openings or ports in the cylinder wall.

The passages or conduits for the operating fluid to and from the valve disc and/or cylinder piston may be formed out of or in conjunction with the valve casing or other cover upon the wall of the cylinder body or by a separate pipe or pipes provided for the purpose.

The conduit or passage or passages may be provided with taps, stops, plugs or valves or any. other suitable devices or combinav.tion of devices for the purpose of varying at will the point of passage of the operating fluid from the piston chamber through the cylinder or wall to the disc to be operated as the piston alternately opens or closes these ports as it travels to and fro in the cylinder the distance of said travel being regulated as the tap or other devices are set or adjusted from time to time by hand or automatically.

In a practical application to a pile driver or extractor the piston may travel upon a central rod or rods one of them being fixed and solid and having a striking block at tached to or forming part of the central rod and closing one end of the cylinder,

made fluid tight by means of piston rings the other end of the rod passing through a gland in the cylinder cover at the opposite.

end, and shock absorbing spring means may be provided upon it, suitably retained in position.

Other devices may be attached such as grips for use in lifting or the cross head of a pump or compressor.

In order that the invention may be readily'understood, reference is made to the accompanying drawings, which show one construction according to the invention in which:

Fig. 1 is a longitudinal section of the cylinder and piston.

Fig. 2 is a similar view showing the piston at the opposite end of its stroke.

Fig. 3 is a sectional view, on the line 33 of Fig. 4 showing the valve mechanism on a larger scale.

Fig. 4 is an end view of Fig. 3 partly in section.

Fig. 5 shows a modified construction in which the operating fluid is admitted to the cylinder through the central hollow rod.

Fig. 6 shows a further modification in which two hollow central rods are employed.

Fig. 7 shows a modified construction of the piston or monkey.

Fig. 8 shows a construction in which the central rod is dispensed with.

The cylinder 1 is formed with a flanged head 2 to which is bolted or otherwise secured a cover plate 3. The opposite end of the cylinder is provided with a striking or anvil block 4, a portion of which extends within the bore of the cylinder at 5, and is rendered steam tight therein by one or more piston rings 6. This striking block. is formed integral with or has attached thereto a rod 7 extending through the centre of the cylinder and through a gland 8 provided in the cover plate 3, a shock absorbing spring or springs 9 being provided between the top of the cylinder cover and stop 10 retained by a nut 11 screwed on to the rod 7. The outer end of the rod is preferably screwed at 12, for attachment of tackle or grips when the apparatus is used for extracting piles.

The piston or monkey 13' is cut away at 1 1, to form a chamber for the passage of steam or other operating fluid from the ports nicates with the interior of the cylinder through a number of ports 20. Those ports are arranged at spaced intervals longitudinally of the cylinder and are each provided with separate cocks, stops, or the like 21 by means of which any of the ports may be closed as desiredin order to vary the point of admission of the operating fluid to the valve casing and thus vary the stroke. The inlet passage 16 is preferably located adja cent the valve casing but is shown in Figs.

1 and 2 of the drawings on the opposite side of the cylinder for the sake of clearness.

Referring now to Figs. 3 and 4, the valve casing 23 is of any appropriate construction and may be formed with or separately attached to the wall of the cylinder. The valve comprises two discs or drums, 2-1 and 25 connected by a spindle 26. The discs are preferablv so attached thereto that they can be readily separated and removed from the casing, the spindle 26 being preferably of smaller diameter than the discs. I

The discs 24 and 25 are each formed with a plurality of pockets or recesses 27 extending around a portion of their peripheries, each balancing the other, that is, the pockets are arranged to co-operate with the operating fluid, entering through the port 27 in the valve chamber, so as to rotate the valve in opposite directions, the portions of the periphery of said discs opposite the pockets, each being cut away or formed with a circumferential slot, 28 to form a recess'engaging a stop or stops 29 secured to the casing for limiting the rotary movement of the valve. extending from or communicating at one end with one or more of the pockets 27 and at the opposite end with thecircuinterential recess 28. This passage allows a small quantity of operating fluid to. cushion the shoulder 28 at the end of the recess 28 against the stop 29.

The spindle 26 is formed with two passages 31 and 32, extending transversely through said spindle and parallel with one another, and two similar passages 33, 34 extending at right angles to the passages 31 and The passages32 and 33 constitute ports through which steam is conveyed: from the chamber 35, formed in the valve casing,

said chamber being supplied with steam through a pipe or pipes not shown,secured to the inlet port 36. p

The spindle'26 is rendered fluid tight within its casing by a plurality of piston rings 37, arranged between the transverse passages 31, 32, 33and 34, and between the discs 24 and 25 and the adjacent passages 31 and 34 respectively.

The operating fluid is conveyed from the valve casing through'the respective ports to each end of the cylinder to operate the piston or monkey by two preferably forked pipes 38 and 39. The forked ends 38 of the pipe 38 are secured in any suitable manner to the valve casing so as to" register with the pas sages 32 and 34. The pipe 38 is connected to the fluid passage 40 in the cylinder walls (Figs. 1 and 2), opening-to the end of the;

cylinder, whilst the pipe 39 is connected to the passage 41, opening into the opposite end of the cylinder. 43 are cover plates bolted or otherwise suitably attached tothe ends'of the valve casing 23 in a" fluid tight manner.

44 is an exhaust passage in the wallet the casing, for the fluid operating the valve whilst 45, 45, are exhaust portsin the casing for the piston operating fluid, said ports being preferably located opposite to one of the torked'ends,38 or 39 of the pipes 38' and 39 respectively.

The operation is as follows:

The valve chamber 35 is supplied with steam or other operatmg fluid through a pipe or pipes connected to the port 36. Part of the fluid passes through the passage 16 and one of the ports 15 to the annular chamber 14, formed in the piston or monkey. fNow assuming the piston to be in the position shown in Fig. 1, the steam passes froni the chant. ber 14, through the passage 19 in the cylinder i walls, throu'gh'the port 27 from-which it 30 is a passage across the discs the valve spindle, the valve is rotated opening the passage way 33, to the chamber 35,in the valve casing and simultaneouslyclosing of the cylinder beneath the piston causing the latter to rise within the cylinder. In rising the passage of the steam to the pockets 27, in the di'sc24 is cut oil owing to the piston covering the passage" 19.

The piston now rises until the chamber 14, therein comes opposite to one of the ports 20, the cock 21, of which is in its open position, in Figs. 1 and 2 iti's assumed that the uppermost port 2O is open whilst the two intermediate ports are closed. piston has now reached the, position shown in Fig. 2, and steam isforced through the passage 19 from which it is transmitted to the valve casing and enters a corresponding port registering with the pockets 27 in the disc 25. The valve is now rotated in the opposite direction causing the'passage 33 to be closed whereby the steam is cut off from the underside of the piston whilst simul taneously the, passage31 is opened to exhaust through the port 35, as shown in Fig. 3; This rotation of the valve alsopl'aces the chamber 35 in the valve casing in communication with the top of the cylinder through the passage 32, pipe39 and the passageway '41, in the walls of the cylinder the fluid entering above the piston under pressure forcing the piston down until it strikes the striking block 4, the lower end of the cylinder exhausting through the passage 40, in the cylinder walls, pipe 38, passageway 31, and thence through the port 45, to the atmosphere. lVlien the piston againrises, the exhaustfrom the chamber above the piston is exhausted through the passage 41,

produced between the end 28 of the passage 8 28 and the slot 29, the fluid finally discharging through the port 44.

The discs 24 and 25 on the ends of the valve spindle if necessary be formed with passageways 49 communicating with the exhaust passages 31 and 34, respectively through which the fluid for operating the valve escapes. I l

" The cylinder is provided with two or more The impinges against the walls of the pockets 27 in the disc 24. The disc beingconnected to longitudinal rods or bars 51, shown in chain lines in Fig. 1. These rods are formed with eyes, hooks,'rings, or the like at each end preferablypassed through holes or perforations in the cover plate 3, the flanged end 2 and an annularflange 50, located a short distance from the opposite end of the cylinder. When the apparatus is used for pile driving or the like operations, the machine is sup"- .ported bychains. cables or the'like, from the members 52 whilst when the machineis to be used for pile extracting, it is merely necessary to invert the machine so that the members 52 become uppermost whilst the grips of other tackle are screwed onto the end 12 of the central shaft and the apparatus is ready for operation.

In the construction shown in Fig. 5, the central rod 7 on which the piston slides is .rna'de hollow to serve as a passage 53 for the admission of operating fluid. This passage is provided with two longitudinal slots 54, 55, whilst the piston or money 13 is provided with two radial ports 56,57 communieating with the annular chamber 14. The

cylinder cover plate 3 may be provided 6O is formed integral with orattached to the anvil block 4 and is provided with a series of ports 61, spaced apart longitudinally of the rod. Vithin this rod is mounted a partly hollow rod 62, provided with ports 63 arranged at spaced intervals apart but each displaced angularly relatively to one another. The iston or monkey 13 which is a sliding fit on the outer tube or rod 60 is provided with an inner annular chamber 64 com- 'municating with the outer annular chamber 14 through one or more radial passages 64 The lower end of the rod 62 is formed with a head 65 which may be formed square or any other shape according to the number of ports, adapted to engage a correspondingly shaped recess 66 closed by a screwed plug 67 or other suitable'means. In Fig. 6, the inner hollow rod is in a position in which its uppermost port 63 registers with the uppermost port 61 of the outer rod 60. 'The lowerend of the rod'62 is provided with ports 68 arranged in the same'transverse plane but displaced angularly relatively to one another by 90. These ports register with a port 61 n the outer rod 60. With the construction shown the valve operating fluid is admitted through the inner rod 62- and passes through the orts 68 and 61 to the annular chamber 64 t ence to the outer chamber 14 to the passage 19 and thence to the valve. The latter is now reversed causing the operating fluid to be transmitted through the passage 40 to the lower end of the cylinder. The piston or monkey 13 is now moved upwardly to the position shown, in dotted lines. 'As soon as the upper endof the inner chamber 64 registers with the uppermost port 61 (or any other port which is open), the valve operating fluid is placed in communication with and reverses the valve through the passages 63 and 61, chamber 64, passage 64 ghamber 14, passage 20 to the valve chamer.. I

Fig. 7 shows a modified onstruction of p ston or monkey, in which its outer periphery isformed with two annular chambers 14 cooperating with the inlet ports 15 and the passages leading to the valve chamber. The operation is similar to that first described and needs no further description.

In the construction shown in Fig. 8, the central rod and the annular chamber in the piston 13, are dispensed with. In this form the cylinder walls are provided with passages 68, 69 leading to ports arranged at opposite endsof the cylinder. Between the ports, passages 70, 71 are provided which are located in such a position that they are alternately uncovered by the piston 13 on the latter reaching the end of its stroke, or preferably immediately before it reaches these positions. The operation will be read ily understood. The passages being connected to the valve chamber steam is transmitted say -to the passage 69, the passage 68 being open to exhaust when the piston is in the position shown in Fig. 8. The piston is now raised by the fluid admitted to its underside. As soon as the lower end of the piston 13 uncovers the passage 71, the fluid is admitted to one of the passages 27* of the valve whereby the latter is rotated to its reverse-position, the passage 69 being opened to exhaust whilst the passage 68 is opened to the admission of fluid above the piston. The latter now moves downwardly until the passage is uncovered by the upper end of the piston whereby the valve is again reversed.

In general the invention may be modified in various ways without departing from the principle thereof.

What I claim as my invention and desire to secure by Letters Patent of the United States of America is 1. Apparatus for controlling the movement of pistons for operating pile drivers, pile" extractors, hammers. and the like anparatus. comprising a cylinder, passages in said. cylinder communicating with a valve chamber, a plurality of separately closable ports arranged longitudinally of said cylinder and communicating with one of said passages, a piston or monkey reciprocating within said cylinder, at least one annular chamber, in the periphery of said piston cooperating with said ports, a valve rotatably mounted in said valve chamber, discs on the ends of said valve, peripheral pockets disposed in opposite directions in each of said discs against which operating fluid is directed through passages in said cylinder, and transverse ports in said valve through which the operating fluid is alternately admitted to and emitted from opposite ends of said cylinder.

2. Apparatus for controlling the move ment of pistons for operating pile drivers, pile extractors, hammers and the like apparatus, comprising a cylinder, passages in said cylinder communicating with a valve chamber, a plurality of separately closable ports arranged longitudinally of said cylinder and communicating with one of said passages, a piston or monkey reciprocating within said cylinder, at least one annular chamber in the periphery of said piston cooperating with said ports, a valve rotatably mounted in said valve chamber, discs on the ends of said valve, peripheral pockets in each of said discs, circumferential slots in the discs located diametrically opposite said pockets, a passage between said slot and the said pocket in each disc, a stop extending into said slots to limit the rotary movement of said valve and transverse ports in said valve through which the operating fluid is alternately admitted to and emitted from opposite ends of said cylinder.

In testimony whereof I affix my signature.

RICHARD HENRY ANNISON. 

